What is the logic of marbles in medium practice section…how it can be (n-1)C(k-1)??..pls help…thanks
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Just two days back even i was wondering the same… when i found this
and please go through Wikipedia. It contains detailed explanation.
It’ll surely help…!!!
Reali thanks…this qstion was disturbing me for two days…
You can use the popular Beggar’s method (is usually taught in High Schools).
Distribution of n-k coins to k beggars.
For distribution of r identical coins among n beggars is c(n+r-1,r-1)
Applying the formula you get required the formula